C,C'-azodi(formamide)

Endpoint summary

Additional information

Short-term toxicity to fish

One study is available and valid.

In a 96-h acute toxicity study, Fathead minnows (Pimephales promelas) (10/group) were exposed to azodicarbonamide (ADCA) at nominal concentration of 0 (control, in duplicate) and 50mg/l (highest dose possible due to solubility, in triplicate) under semi-static conditions (Safepharm 1992, report 445/6). 

There were no mortalities or other adverse reactions to exposure in the exposed 30 fishes. The 96-h LC50, EC50 and NOEC values were higher than 50mg/l, based on mortality. 

This toxicity study is classified as acceptable and fully satisfies the guideline requirement for short-term toxicity to fish.

Long term toxicity to fish

This study is waived.

Short-term toxicity to aquatic invertebrates

One study is available and valid.

The 48–h-acute toxicity of Azodicarbonamide (ADCA) to Daphnia magna was studied under static conditions (Safepharm 1992, report 445/5).  Daphnids were exposed to control and test chemical at nominal concentration 0.50, 0.90, 1.6, 2.8, 5.0, 9.0, 16, 28 and 50mg/l for 48h.  Mortality/immobilization and sublethal effects were observed daily and at test termination. 

The 24h-NOEC and 48h-NOEC based on immobilization were 4.8 and 4.8 mg/l, respectively. The EC50 in daphnia magnia immobilisation test were 12 and 11 mg/l at 24 and 48 h, respectively. 

This study is classified as acceptable and satisfies the guideline requirements for an acute toxicity study with freshwater invertebrates.

Long-term toxicity to aquatic invertebrates

The prolonged toxicity of Azodicarbonamide (ADCA) to Daphnia magna was studied under semi-static conditions.  Daphnids were exposed to control and test chemical at nominal concentration 0.315, 1.01, 3.22, 10.3 and 33 mg/L for 21 days.  Survival of the parental Daphnia, sublethal effects on the parental generation and neonatal production were observed daily and at test termination. 

The 21-d NOEC was determined as 2.89 mg/L for reproduction and 9.19 mg/L for both parental mortality and growth. The overall NOEC was found to be 2.89mg/L. 

This study is classified as acceptable and satisfies the guideline requirements for a prolonged toxicity study with freshwater invertebrates

Toxicity to aquatic algae and cyanobacteria

An algal growth inhibition test was conducted by Bayer AG, Germany, to determine the effect of the test substance Azodicarbonamide on the aquatic environment. The study was conducted in compliance with GLP, and was performed according to EC test guideline C3 (Bayer 1998).

The biomass increase and growth rate of a culture of algae (scenedesmus subspicatus) was monitored over a period of 72 hours in growth media containing a series of concentrations of the test substance. Test substance concentrations assesed were 0 (control), 5, 10, 20, 40, and 80 mg/L.

The 72-hour E_rC₅₀of the test substance ADCA in algae was determined to be greater than 36.1 mg/L.

Toxicity to aquatic plants other than algae

No data available. No data required.

Toxicity to microorganisms

The effect of azodicarbonamide on the respiration rate of activated sludge was assessed by the methods detailed in and OECD Test Guideline 209 and in compliance with GLP (HLS 2010, LBA0004).

The three-hour EC50 for azodicarbonamide was calculated to be 800 mg/L (95% confidence limits, 312 to 3230 mg/L).

The EC20 was calculated to be 26 mg/L (95% confidence limits, 2.2 to 129 mg/L). The EC80 could not be calculated as this was greater than 1000 mg/L, the highest concentration tested.

Toxicity to other microorganisms

No data available. No data required.

Conclusion

The most sensitive trophic level is the aquatic invertebrate (Daphnia).